<h2>DESCRIPTION</h2>

<em>v.lrs.where</em> identifies line id and real milepost+offset for
points in vector map using linear reference system.

<h2>EXAMPLE</h2>

This example is written for the Spearfish dataset (it continues the example
from <em>v.lrs.create</em>).
<p>
In this example, the 'route_lrs' shall be queried for unknown
positions (points, stored in the map <em>newpoints</em>) along the LRS:

<div class="code"><pre>
# generate query points
echo "590866.15|4926737.0
590933|4927133" | v.in.ascii out=newpoints

v.lrs.where lines=route_lrs points=newpoints rstable=route_lrs
pcat|lid|mpost|offset
pcat|lid|mpost|offset
1|22|4.000000+212.091461
2|22|6.000000+188.112093

# verification
g.region vector=route_lrs n=n+100 s=s-100 -p
d.erase
d.vect route_lrs
d.vect busstops disp=attr attr=cat size=10 bg=white lcol=blue yref=bottom
d.vect busstops icon=basic/circle fcol=blue
d.vect newpoints col=red

# measure distance to previous bus stop:
# use measuring tool in graphical user interface
</pre></div>

<h2>SEE ALSO</h2>

<em><a href="lrs.html">LRS tutorial</a></em>,<br>
<em><a href="http://gisws.media.osaka-cu.ac.jp/grass04/viewpaper.php?id=50">Introducing the Linear Reference System in GRASS</a></em>,<br>
<em><a href="v.lrs.create.html">v.lrs.where</a></em>,
<em><a href="v.lrs.segment.html">v.lrs.segment</a></em>,
<em><a href="v.lrs.label.html">v.lrs.label</a></em>

<h2>AUTHOR</h2>

Radim Blazek, ITC-irst/MPA Solutions<br>
Documentation update (based on above journal article and available fragments): Markus Neteler

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